Solve for $x$ and $y$ using substitution. ${-6x-6y = -6}$ ${x = 3y+9}$
Explanation: Since $x$ has already been solved for, substitute $3y+9$ for $x$ in the first equation. ${-6}{(3y+9)}{- 6y = -6}$ Simplify and solve for $y$ $-18y-54 - 6y = -6$ $-24y-54 = -6$ $-24y-54{+54} = -6{+54}$ $-24y = 48$ $\dfrac{-24y}{{-24}} = \dfrac{48}{{-24}}$ ${y = -2}$ Now that you know ${y = -2}$ , plug it back into $\thinspace {x = 3y+9}\thinspace$ to find $x$ ${x = 3}{(-2)}{ + 9}$ $x = -6 + 9$ ${x = 3}$ You can also plug ${y = -2}$ into $\thinspace {-6x-6y = -6}\thinspace$ and get the same answer for $x$ : ${-6x - 6}{(-2)}{= -6}$ ${x = 3}$